My buddy Justin Eldridge uses a copper bus bar. Sounds like the same thing you have to use.
He is one of the best knappers i know and dose very well with it.
If i were you id try to make it to a knap-in or look up a local knapper in your area to get some 1on1 help.
if that dose not work out then check out the youtube vids.
Might be worth it to ya to look at
www.flintknappingtools.com Mark has some nice kits for sell there with most of what ya need to get started.